Oregon
Oregon is a state in the Pacific Northwest region of the United States. Oregon borders the Pacific Ocean on the west, Washington on the north, Idaho on the east, and California and Nevada on the south. The Columbia and Snake Rivers form, respectively, much of its northern and eastern borders. Between two north-south mountain ranges in western Oregon—the Oregon Coast Range and the Cascade Mountain Range—lies the Willamette Valley, the most densely populated and agriculturally productive region of the state.
Oregon has one of the most diverse landscapes of any state in the U.S. It is well known for its tall, dense forests; its accessible and scenic Pacific coastline; and its rugged, glaciated Cascade volcanoes. Other areas include semiarid scrublands, prairies, and deserts that cover approximately half the state in eastern and north-central Oregon.
Oregon's population in 2000 was about 3.5 million, a 20.3% increase over 1990. It is estimated to have reached 3.7 million by 2006
Geography
Oregon's geography may be split roughly into seven areas:
- Oregon Coast—west of the Coast Range
- Willamette Valley
- Rogue Valley
- Cascade Mountains
- Klamath Mountains
- Columbia River Plateau
- Basin and Range Region
The mountainous regions of western Oregon were formed by the volcanic activity of Juan de Fuca Plate, a tectonic plate that poses a continued threat of volcanic activity and earthquakes in the region. The most recent major activity was the 1700 Cascadia earthquake; Washington's Mount St. Helens erupted in 1980, an event which was visible from Portland.
The Columbia River, which constitutes much of the northern border of Oregon, also played a major role in the region's geological evolution, as well as its economic and cultural development. The Columbia is one of North America's largest rivers, and the only river to cut through the Cascades. About 15,000 years ago, the Columbia repeatedly flooded much of Oregon during the Missoula Floods; the modern fertility of the Willamette Valley is largely a result of those floods. Plentiful salmon made parts of the river, such as Celilo Falls, hubs of economic activity for thousands of years. In the 20th century, numerous hydroelectric dams were constructed along the Columbia, with major impacts on salmon, transportation and commerce, electric power, and flood control.
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It uses material from the Wikipedia article "Oregon"